基于最大比传输预编码天线分组技术的大规模多入多出系统能效研究

Research on energy efficiency of massiveMIMO system based on maximum ratio transmission precoding antenna grouping technology

大规模多输入多输出(MIMO)系统中,大型天线阵列之间的强天线相关性会导致系统性能降低.针对下行链路场景,提出基于最大比传输预编码的联合天线分组和天线选择算法,把大规模天线阵列划分为若干组,在每组中基于信道矩阵最大列范数选择天线,构造所选天线与接收天线间的信道矩阵,并计算对应的预编码矩阵.建立能效模型,分析联合天线分组和天线选择算法对系统能效的影响.仿真结果表明,在基站天线数为200、发射功率为10 dB、天线相关因子为0.8的假设下,当分组数为24时,与最大范数天线选择算法相比,该算法使系统能效提高了约24.4%.

In massive MIMO systems,the strong antenna correlation among large antenna arrays would lead to system performance degradation.In this paper a joint antenna grouping and antenna selection algorithm based on maximum ratio transmission precoding was proposed in regard to the downlink scenario in which the large-scale antenna array was divided into several groups.In each group,the antenna was selected based on the maximum column norm of the channel matrix.The channel matrix between the selected antenna and the receiving antenna was constructed,and the corresponding precoding matrix was calculated.Finally,an energy efficiency model was established to analyse the influence of both joint antenna grouping and antenna selection algorithm on energy efficiency of the system.The simulation results showed that under the assumption that the number of base station antennas was 200,the transmission power was 10 dB,and the antenna correlation factor was 0.8,when the number of packets was 24,comparing with the maximum norm antenna selection algorithm,the proposed algorithm was able to improve the system energy efficiency nearly by 24.4%.